Failure to generate user instance of SQL Server error, when setup application is run

[Avrajit]

Hi,
I am unable to run my c# application on a different computer other than my own computer. I have an attached mdf database file in my project. I have 'SQL SERVER 2008' as pre-requisite in the setup project. The application is installing & running fine on my machine, but when i install and run it on another machine, it shows the following error:
" Description:
Stopped working

Problem signature:
Problem Event Name: CLR20r3
Problem Signature 01: esbi.exe
Problem Signature 02: 1.0.0.0
Problem Signature 03: 4dd8feca
Problem Signature 04: System.Data
Problem Signature 05: 2.0.0.0
Problem Signature 06: 4a274a01
Problem Signature 07: 2744
Problem Signature 08: 11
Problem Signature 09: System.Data.SqlClient.Sql
OS Version: 6.1.7600.2.0.0.256.1
Locale ID: 1033 "

So, I planted a try-catch block on the first opening of connection to the database & caught the following error:
" System.Data.SqlClient.SqlException: Failed to generate a user interface of SQL Server due to a failure in starting the process for the user instance. The connection will be closed. "

The connection string i am using to connect to the database is
" Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\esbi.mdf;Integrated Security=True;User Instance=True "

what am i doing wrong?? Is it something with the connection string??
Please help.

with regards,
avrajit

[Momerath]

You need to install SQLExpress on the machine. It runs as a service when needed, thus the '... due to a failure in starting the process ...'

[Avrajit]

Hi Momerath,
I have SQL Express as a pre-requisite. It gets installed before the application does.